Strainer for tube wells or the like



Feb. 22 Q .1927.

I a LEGGETT STRAINER FORTUBE WELLS OR THE LIKE 2 Shasta-Shot xf; 6 1 15.

Filed May 16. 1924 Feb. 22, 1927. 7 1,618,837:

, s. LEGGETT STRAINER FOR TUBE WELLS OR THE LIKE Filed 14127116. 1924 2 Sheets-Shoot 2 F7 ,6, F! J: v r 4 J 7 Patented Feb. 22, 1927.

UNITED STATES PATENT OFFICE.

STEPHEN LEGGETT, OF AMRITSAR, BRITISH INDIA.

STRAINER FOR TUBE WELLS on'rHn LIKE.

Application filed May 16, 1924, Serial .No. 713,706, and in India October 27, 1923.

7 .My invention consists in an improved strainer for tube wells or the like, which are embedded in the soil, and my invention particularly consists in the combination with a strainer of a cleaning, device so arranged as to be operated mechanically in suitable time intervals to keep the openings of the .strainer from becoming clogged up.

A great difiiculty experienced with tube wells embedded in the soil is that the flow .of Water gradually decreases and in the course of several years becomes materially reduced due to the clogging of'the strainer. Experience shows that in many cases the clogging is due to a hard deposit 'of mineral matter forming on and in the interstices of the strainer. This deposit is in most cases quite thin-perhaps not more than 5 thick after many years servicebut as it forms upon the strainer itself, it has a material effect on the percolation. of the water into the tube Well since it tendsto close colation openings. Various devices the fine perhave been suggested for cleaning the strainer. In someof these devices, a cleaner is lowered into the tube well and expanded to enter into the percolation slits and then is worked in these slits to clean them. These devices however, labor underthe disadvantagethat it is difiicult to 7 ensure that the cleaning blades will enter the slits, because, owing to the fineness of said slits, it is generally considered advisable to I provide several blades to simultaneously! 12, the strainer consists of a plurality of sec-.

tions 'or units, each comprising a number of, wire rings A. preferably of trapezoidal nently in the slits, being mounted in multi- Y .[ples on suitable frames and adapted to be moved or rotated; However, the frameworks or cages project into the interior of the tube and thus offer a material frictional resistance to the flow of the liquid therethrough.

In the caseof deep wells, sueh additional resistance, is qu te important.

' Now} according to' my invention, the

strainer is built'about, or placed around,.the central tube of thewell which is of relatively largediameter-and is equipped with I cleaning means which remain permanently in place. The parts whereby thecleaning means may be operated project through openings into the central tube, but'only a short .distance so as not to interfere with the flow of liquid. The strainer comprises preferably a plurality of SlIPGI'POSQd lDdP' vidual wire rings separated byspacers and; 7

supported by a skeleton frame, but the strainer may also consist. of a continuous wire helix supported by ,a frame. 'Or, the strainer may be. formed of a cylindrical outer tube of large diameter having pro-..,

vided slits therein. In anycase, the operat-' ing members of the cleaning device extend into the spaces provided between the parts of the strainer, or the slots, so as'to clean the same, when the cleaning device is operated.

The cleaning device preferably apertures in the central tube whereby the cleaning device the strainer.

equipped .with parts engageable through maybe moved relatively to The strainer is preferably made in sec- 7 tions or units surrounding. the central .tube, and preferably, each section r unit is separately supported.

Fig. 5 is a section on an enlarged scale, along .l1ne55.and Fig.6 a similar sectlonshow In the accompanyingdrawings, in which like letters of reference'indicate] like parts,

ingthestrain'er construction, Fig. 7 a similar section showing adifi'erent strainer.

In the embodiment shown in F1gs.,1 and each two adjacent wire ri'ngs. The latter are placed overfla strainer body or frame composed of T or angle Jbars J riveted to the tube F. The cleaning-means comprise annular end plates D surrounding, but sep-' 7 'arate from, the tubeF, the main longitudinal bars H and rods C connecting said end plates D inipairs forming cages. .Mounted on the vertical rods ,0 of each cage are, rotatablecircular discs E, which protrude between-the wire rings A' of the strainer projecting outwardly to a small extent.

The bars J support the separate cleaning on the upper sections, the plates D resting ends of. the ,bars.

The various cages are free to turnabout.

the central tube F, which is the main support of the strainer structure, and forms the well.

The tube F has apertures G, allowing movement of the lugs H, H, carried by the longitudinal bars H ofe'a'ch cage, as the latter are turned in either direction by means of said projections. The wire rings A are secured to stops J, J, which are in short lengths and are secured to the central tubes -F between th'eend'plates D of each cage, so that "the wire rings are held stationary in relation to the tube F.

The discs E are virtually like the teeth of F a "revolving comb, progressing with a circula'r motion about the axis of tube F, and

7 also turningon their-own axes.

The travel of the cagesand comb teeth is limited to "ojt a revolution in the example illustrated-in Figsal to 3 inclusive.

-It will be seen that the causes of diminishing supply are dealt within one operation. The comb teeth, or discs E on beingmoved backwards and forwards clean theapertures or slits in the strainer and also cut through the thin crust which forms on the outside,

7 while the bars C and H of the cage remove the muddy matter which clogs the annular space between the strainer and the tube, all

in a simple and mechanical manner.

'In Figures 3 and a a coupling for two strainer sections is illustrated. To the end of each length of the central tube a jointing ring K is bolted or otherwise secured. These jointing rings may be provided with ag'roove A channel shapedjointing strip M is l t-hen pressed into two adjacent groov'es L,-L,

holding thesec-tions of the tube firmly to- .gether. A/fish-plate N may be riveted, or otherwise fixed, to cover the joint'in the stripN.

It willbenoticed'thatthe rotatable cages occupy -a,sm'al1radial depth, enabling a central tube of large diameter tobe used for;

the flow ofjthe water, and what is 01"; im-

, portance, this tubecpposes onlyja lowfriction'al resistance meow, not much greater than that possessed by a smooth steel pipe.

The strainer is in no way inferior to strainers not equipped with means for cleaning the slits, the supply of water is not less than with the latter, and the construction is strong and'robust, not easily damaged during'installation,

It is expected that the cleaners will require to be operated once a year to keep the slits free from deposits, two days being sufficient forthisp'rocess; v, g 1

In Figures 5 and 6, fragmental sections on an enlarged scalesh' w one. "form which the combined strainer. and'cleaner may take. In "these figures the straining envelope is "formed of a plurality of wirerings A supported on stops J secured to the central tube F.'

The cleaner comprises a cage or frame of units of convenient lengths as indicated in Fig. 2. Heavy vertical lon git'i' d'injal members H, H connect the end rings 1), of each cleaner section and nave eprojections H, H which enablethe cleaner to be mfoved backwards and forwards 'circumie'rentially in the slots of the strainer.

Figure 7 corresponds to -F1;'g' ufre'5 except that-the strainer in this embodiment eonsis-ts of a helix A of wire, instead "o'fbe'in made up of separate rings. a

It is, of course, understood thatI 'dofnot confine myself to the embodiments described with reference to the drawings, but claim any reasonable modifications. For instance,

the straining envelope may be spirally wound 1n sect1o'ns, and if desired, "a strainer having inclined -percolati'on slits may be used; In the embodiment shown in Figs 13, the cleanin'gope'ration is' pertormed by rotatin the cage through "an angle of about 45 but if the slots are ver tical or inclined, an up and down motion may be give or a combined rotational and longitudinal motion. V I

I claim: v

1. The combination with a tube. e811,

adapted to be "embedded 'in the *soil,,"'of a;

straining device surrounding, and supported by, a central tube, and cleaning means ipermanen'tly situated between the 'saidstraining j device and said tube and having parts extending into. the openings ofTthe Said 'strain-v ing device, and meansfor in ving fth e said" cleaning means and straining device: "rela tively to each other.

2. The combination with a tube welil, at a straining device surrounding a tube of 'relartively large dla-m'eter forming the inner frame of the straining device,c l-"eaningn1eans extending permanently into the,. percol ation openings of thesaid strainingdevice, means for moving the said cleaning 'means relative to the-said strainin "device. 7 v

3. The combination with .atube wen, of a straining device surrounding, "and "supported a tube, cleaning means extending permanently into the percolation openings in the said straining devicepand means for moving the said cleaning me'ans relative to the said. straining device.

The combination with fa' tu be of a straining device surroundmg', and sup ported by a tube, movablel eieaningmeans extending permanently into the-f'perc'oiation openings in the said straining device, and

means for moving the said cleaning means relative tothe said straining device, the said tube having apertures wherethrough liquid passing through the said straining device may pass from the annular space be tween said device andtube into the latter.

5. The combination with a tube well, of a straining device surrounding a tube, movable cleaning means extending permanently into the percolation openings in the said straining device, lugs (H) provided on said cleaning means and engageable through apertures in the said tube, whereby the said cleaning means may be moved relative to the said straining device.

6. The combination as specified in claim 1, in which the cleaning means comprises a cage composed of rings and longitudinal members, and carrying cleaning parts extending through the percolation openings in the said straining device.

7. The combination with a tube well, of a.

straining device surrounding, and supported by, an inner tube, cleaning means extending permanently into the percolation openings 'in the said straining device, ears on said cleaning means engageable through apertures in the. said tube for moving the said cleaning means relative 'to thesaid straining device, the said cleaning means comprising a cage composed of individual members having projections adaptedfto pass through the percolation openings in the said straining device.

8. The combination as specified in claim 1, in which the straining device is formed of aseries of sections positioned on tube sections, and means connecting the adjacent tube sections.

9. The combmation as specified 1n clalm 1,

in which the straining device is formed of a series of sections positioned on said tube, and means for separately supporting each section. y

10. The combination as specified in claim 1, in which the said straining device consists of a helix of wire, and spacers extending between the various convolutions.

11. The combination with a tube well, of

a straining device and cleaning means therea frame mounted on said tube, a straining device formed of sections supported on the sald frame, cleaning cages formed of rings and longitudinal bars, cleaning cutter discs rotatably mounted on the said longitudinal bars, and extending into the percolation slits between the said rings, ears attached to the said cleaning means and projecting through said'apertu-res into the said tube without interfering with the passage of liquid therethrough, the said ears being adapted to be mg means relative to the said straining device in either direction.

In testimony whereof I hereto affix my signature, this eleventh day of April, 1924. i STEPHEN'LEGGETT.

.70 engaged by'a tool for moving the said clean- V 

